linux-kernel - [PATCH 5.10 01/39] KVM: PPC: Book3S HV: Context tracking exit guest context before enabling irqs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 21 Sep 2022 17:46:06 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Nicholas Piggin <npiggin@...il.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 01/39] KVM: PPC: Book3S HV: Context tracking exit guest context before enabling irqs

From: Nicholas Piggin <npiggin@...il.com>

[ Upstream commit 112665286d08c87e66d699e7cba43c1497ad165f ]

Interrupts that occur in kernel mode expect that context tracking
is set to kernel. Enabling local irqs before context tracking
switches from guest to host means interrupts can come in and trigger
warnings about wrong context, and possibly worse.

Signed-off-by: Nicholas Piggin <npiggin@...il.com>
Signed-off-by: Michael Ellerman <mpe@...erman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-3-npiggin@gmail.com
Stable-dep-of: 235cee162459 ("KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling")
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/powerpc/kvm/book3s_hv.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 38b7a3491aac..d6c4e27f7ed9 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3399,8 +3399,9 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 
 	kvmppc_set_host_core(pcpu);
 
+	guest_exit_irqoff();
+
 	local_irq_enable();
-	guest_exit();
 
 	/* Let secondaries go back to the offline loop */
 	for (i = 0; i < controlled_threads; ++i) {
@@ -4235,8 +4236,9 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
 
 	kvmppc_set_host_core(pcpu);
 
+	guest_exit_irqoff();
+
 	local_irq_enable();
-	guest_exit();
 
 	cpumask_clear_cpu(pcpu, &kvm->arch.cpu_in_guest);
 
-- 
2.35.1